Auriculin anaritide [atrial natruritic factor ANP)] may improve oliguric acute tubular necrosis (ATN). The purpose of this study is to provide a more indepth study of those patients with oliguric ATN to determine if ANP can decrease the need for dialysis and improve survival. This is a multicenter prospective randomized controlled study. We are currently recruiting patients. One subject is enrolled. This used BIOSTATISTICIAN ONLY.